vserver 1.9.5.x5

[linux-2.6.git] / arch / arm / mm / consistent.c

diff --git a/arch/arm/mm/consistent.c b/arch/arm/mm/consistent.c
index 57b0be2..915cee5 100644 (file)
--- a/arch/arm/mm/consistent.c
+++ b/arch/arm/mm/consistent.c
@@ -1,7 +1,7 @@
 /*
  *  linux/arch/arm/mm/consistent.c
  *
- *  Copyright (C) 2000-2002 Russell King
+ *  Copyright (C) 2000-2004 Russell King
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
@@ -30,7 +30,7 @@
  * This is the page table (2MB) covering uncached, DMA consistent allocations
  */
 static pte_t *consistent_pte;
-static spinlock_t consistent_lock = SPIN_LOCK_UNLOCKED;
+static DEFINE_SPINLOCK(consistent_lock);
 
 /*
  * VM region handling support.
@@ -65,6 +65,7 @@ struct vm_region {
        struct list_head        vm_list;
        unsigned long           vm_start;
        unsigned long           vm_end;
+       struct page             *vm_pages;
 };
 
 static struct vm_region consistent_head = {
@@ -206,6 +207,8 @@ __dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, int gfp,
                pte_t *pte = consistent_pte + CONSISTENT_OFFSET(c->vm_start);
                struct page *end = page + (1 << order);
 
+               c->vm_pages = page;
+
                /*
                 * Set the "dma handle"
                 */
@@ -215,6 +218,9 @@ __dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, int gfp,
                        BUG_ON(!pte_none(*pte));
 
                        set_page_count(page, 1);
+                       /*
+                        * x86 does not mark the pages reserved...
+                        */
                        SetPageReserved(page);
                        set_pte(pte, mk_pte(page, prot));
                        page++;
@@ -264,6 +270,53 @@ dma_alloc_writecombine(struct device *dev, size_t size, dma_addr_t *handle, int
 }
 EXPORT_SYMBOL(dma_alloc_writecombine);
 
+static int dma_mmap(struct device *dev, struct vm_area_struct *vma,
+                   void *cpu_addr, dma_addr_t dma_addr, size_t size)
+{
+       unsigned long flags, user_size, kern_size;
+       struct vm_region *c;
+       int ret = -ENXIO;
+
+       user_size = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
+
+       spin_lock_irqsave(&consistent_lock, flags);
+       c = vm_region_find(&consistent_head, (unsigned long)cpu_addr);
+       spin_unlock_irqrestore(&consistent_lock, flags);
+
+       if (c) {
+               unsigned long off = vma->vm_pgoff;
+
+               kern_size = (c->vm_end - c->vm_start) >> PAGE_SHIFT;
+
+               if (off < kern_size &&
+                   user_size <= (kern_size - off)) {
+                       vma->vm_flags |= VM_RESERVED;
+                       ret = remap_pfn_range(vma, vma->vm_start,
+                                             page_to_pfn(c->vm_pages) + off,
+                                             user_size << PAGE_SHIFT,
+                                             vma->vm_page_prot);
+               }
+       }
+
+       return ret;
+}
+
+int dma_mmap_coherent(struct device *dev, struct vm_area_struct *vma,
+                     void *cpu_addr, dma_addr_t dma_addr, size_t size)
+{
+       vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+       return dma_mmap(dev, vma, cpu_addr, dma_addr, size);
+}
+EXPORT_SYMBOL(dma_mmap_coherent);
+
+int dma_mmap_writecombine(struct device *dev, struct vm_area_struct *vma,
+                         void *cpu_addr, dma_addr_t dma_addr, size_t size)
+{
+       vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot);
+       return dma_mmap(dev, vma, cpu_addr, dma_addr, size);
+}
+EXPORT_SYMBOL(dma_mmap_writecombine);
+
 /*
  * free a page as defined by the above mapping.
  */
@@ -300,6 +353,10 @@ void dma_free_coherent(struct device *dev, size_t size, void *cpu_addr, dma_addr
 
                        if (pfn_valid(pfn)) {
                                struct page *page = pfn_to_page(pfn);
+
+                               /*
+                                * x86 does not mark the pages reserved...
+                                */
                                ClearPageReserved(page);
 
                                __free_page(page);